Work function tuning of plasma-enhanced atomic layer deposited WC_xN_y electrodes for metal/oxide/semiconductor devices

TY - JOUR

T1 - Work function tuning of plasma-enhanced atomic layer deposited WCxNy electrodes for metal/oxide/semiconductor devices

AU - Zonensain, Oren

AU - Fadida, Sivan

AU - Fisher, Ilanit

AU - Gao, Juwen

AU - Chattopadhyay, Kaushik

AU - Harm, Greg

AU - Mountsier, Tom

AU - Danek, Michal

AU - Eizenberg, Moshe

N1 - Publisher Copyright: © 2015 AIP Publishing LLC.

PY - 2015/2/23

Y1 - 2015/2/23

N2 - One of the main challenges facing the integration of metals as gate electrodes in advanced MOS devices is control over the Fermi level position at the metal/dielectric interface. In this study, we demonstrate the ability to tune the effective work function (EWF) of W-based electrodes by process modifications of the atomic layer deposited (ALD) films. Tungsten carbo-nitrides (WCxNy) films were deposited via plasma-enhanced and/or thermal ALD processes using organometallic precursors. The process modifications enabled us to control the stoichiometry of the WCxNy films. Deposition in hydrogen plasma (without nitrogen based reactant) resulted in a stoichiometry of WC0.4 with primarily W-C chemical bonding, as determined by x-ray photoelectron spectroscopy. These films yielded a relatively low EWF of 4.2-±-0.1-eV. The introduction of nitrogen based reactant to the plasma or the thermal ALD deposition resulted in a stoichiometry of WC0.1N0.6-0.8 with predominantly W-N chemical bonding. These films produced a high EWF of 4.7-±-0.1-eV.

AB - One of the main challenges facing the integration of metals as gate electrodes in advanced MOS devices is control over the Fermi level position at the metal/dielectric interface. In this study, we demonstrate the ability to tune the effective work function (EWF) of W-based electrodes by process modifications of the atomic layer deposited (ALD) films. Tungsten carbo-nitrides (WCxNy) films were deposited via plasma-enhanced and/or thermal ALD processes using organometallic precursors. The process modifications enabled us to control the stoichiometry of the WCxNy films. Deposition in hydrogen plasma (without nitrogen based reactant) resulted in a stoichiometry of WC0.4 with primarily W-C chemical bonding, as determined by x-ray photoelectron spectroscopy. These films yielded a relatively low EWF of 4.2-±-0.1-eV. The introduction of nitrogen based reactant to the plasma or the thermal ALD deposition resulted in a stoichiometry of WC0.1N0.6-0.8 with predominantly W-N chemical bonding. These films produced a high EWF of 4.7-±-0.1-eV.

UR - http://www.scopus.com/inward/record.url?scp=84924078819&partnerID=8YFLogxK

U2 - 10.1063/1.4913715

DO - 10.1063/1.4913715

M3 - 文章

AN - SCOPUS:84924078819

SN - 0003-6951

VL - 106

JO - Applied Physics Letters

JF - Applied Physics Letters

IS - 8

M1 - 082107

ER -